Wallingford’s Lyman Hall High school may become the latest area school to put down artificial turf. The board recently approved a plan for upgrading the school athletic complex that includes a turf field. Across town, Sheehan High School had artificial turf installed in 2006.

In Meriden, teams use an artificial turf field at Falcon Field. Both Cheshire and Southington high schools also have artificial turf fields.

A growing number of studies question how safe the fields are to the students and environment.

Nancy Alderman, president of North Haven-based Environment and Human Health Inc., is cautioning school systems about artificial turf because of environmental concerns posed by the rubber material used to make the turf, know as “fill in.” The fill-in for most fields consists of recycled tires.

“We don’t like the 40,000 ground up tires that are put into the fields,” Alderman said. “Rubber tires have toxins.”

Alderman’s organization completed a study in 2007 that found “tire crumbs and tire mulch release chemical compounds into the air and ground water,” which can cause irritation of the lungs, skin and eyes.

Another study by New Jersey’s Department of Health found the fields in the state contain potentially unhealthy levels of lead dust. The Center for Disease Control and Prevention isn’t certain how much lead is absorbed, but warned that enough could cause neurological problems.

Marc Deptula, buildings and grounds supervisor for Wallingford schools, believes artificial turf fields are safer. The fill-in used in artificial turf “poses no environmental problem at all,” he said.

“I haven’t seen any data on any increases of injuries to players or to the severity of injuries,” Deptula added.

“The artificial turf fields are much more consistent throughout the playing surface.”

With a grass field, there’s a possibility a section of the field can become sos worn down that it is similar to falling down on concrete, Deptula said.

With football and boys and girls soccer teams often using the same fields in inclement weather, area athletic directors have complained that grass fields are unplayable and dangerous because they become so worn.

A number of studies support Deptula’s stance. A three-year study of game-related college football injuries on turf versus natural grass was conducted by Penn State University in 2010. The researchers found “(turf) is in many cases safer than natural grass.”

Another Penn State study, conducted in 2004 featuring high school football players, studied the incidence, causes and severity of high school football injuries on turf and natural grass fields. The five-year study was less conclusive, finding “similarities existed between (turf) and natural grass” and “both surfaces also exhibited unique injury patterns that warrant further investigation.”

But Alderman’s concerns are broader than environmental issues. On a hot summer day the temperature of an artificial turf field can exceed 100 degrees. While a study by the state Department of Public Health in 2010 found this to be true, the agency advised coaches to take precaution on hot days and to install “new crumb rubber in cooler months to avoid the peak exposure that might occur with fresh rubber in the hot weather.”

The Department of Public Health’s study also found no health concerns from inhaling chemicals on outdoor fields. The study also showed “lead levels were low and not a health concern” at the fields investigated.

Despite this, Alderman believes towns should invest in grass fields for practical reasons. Maintaining a grass field is going to be more work, she said, “but it isn’t going to cost the school a million dollars.”

Despite the price tag, school officials often opt for artificial turf, saying the high initial investment is offset by savings on maintenance.

“When you put a synthetic field down, you put down layers of gravel for drainage and layers of other stuff,” she said. “If you ever do that for a nice grass field — if you did a tenth of the layers for a grass field that you put in synthetic fields, think what we’d have.”

When Wallingford was looking into an artificial turf field for Sheehan, Deptula said the board looked into the warnings and concerns. There was debate in Southington for the same reasons, but after the state released its findings, the school system installed an artificial turf field last year.